When initially configuring an Active Directory or LDAP server within StruxureWare DCE, you must first add a server label, address, port, type of server, and the option to use SSL.
The StruxureWare DCE client will then attempt to directly connect to the server. If it is unable to reach the AD or LDAP server at that IP and on that port, it will pop up an error stating "Unable to Reach Host".

Resolution:

This message is not logged in any DCE client or server log. If you are receiving this error, you are either attempting to connect to the wrong server or you are connecting on the wrong port as the client can not see that server type at that address.Please also keep in mind that it is the client attempting to reach the LDAP server at this point in the process so the client computer must be able to connect to the authentication server on the selected port. When the configuration is finished, it is the server that will ultimately have the connection to the authentication server.